BYD B12D

BYD B12D
A BYD B12D was running on route 6
Other Name(s)	BHEV12DL
Manufacturer	BYD Auto
Year manufactured	2022-present
Operator(s)	KMB
Nickname(s)	Double-decker Green BB, Green DD, Large BB, Bed/BED, Bed Bus
Technical information
Length	11.97m
Width	2.55m
Height	4.2m
Floor height	Super low-floor
Weight	24 tonnes
Chassis	BYD
Body	BYD
Motor	Middle axle: BYD EQ13B Front and rear axles: ZF
Battery	BYD 516kWh blade battery
Power output	402hp (2× 150kWh)
Gearbox	No gearbox

BYD B12D (比亞迪B12D) is a double-decker, low-floor electric bus with battery drive produced by BYD Auto in Mainland China. This model is a modified version and successor of BYD K10 and BYD K8S, and is the first major model change project of the manufacturer.

Design

The BYD B12D is an evolution of the single-decker version of the B12A from the same manufacturer. It is available in both left and right-hand drive versions and, like the B12A, is only available in 12-metre lengths.

Chassis

BYD's B12D adopts a dual motorised wheelside drive system, which means that the battery motors are mounted inside the wheels and drive the bus directly, thus eliminating the need for a transmission and driveshaft system and freeing up more space inside the bus. At the same time, the B12D utilises a new generation of batteries and battery management system, which, like the B12A, is based on lithium iron phosphate (LFP) batteries, known as Blade Batteries. The Blade Battery is a smaller cell with a much higher capacity of 516kWh, giving it a range increase of more than 50% compared to existing electric buses in Hong Kong. The battery is mainly installed at the rear of the lower deck, making the lower deck smaller than that of a diesel bus, and the B12D is equipped with a feedback braking system, which converts part of the kinetic energy into electrical energy when the bus decelerates and supplies it to the battery for energy recovery. In addition, the B12D is equipped with a water-cooling system that monitors and adjusts the temperature of the battery and monitors battery performance through the battery management system.

The B12D is powered by a two-shot DC charging system. It takes about 2 hours to charge the bus, and it can cover a distance of up to 300 kilometres, which is sufficient for a full day's travel.

Body

The B12D has an aluminum body designed and assembled by BYD. The lower front end design is similar to the B12A, but the upper licence plate box is designed to be close to the upper front glass to accommodate the height of the lower level, making the overall proportion of the front end not quite balanced. The B12D has two original rear number plate positions, one at the bottom of the upper window to the right, and the other at the rear bumpers, similar to that of Wright Explorer; however, when the bus was registered, the lower reserved position has been cancelled, which is the same as Wright Eclipse Gemini and Wright Eclipse Gemini 2.

Kowloon Motor Bus (KMB) fleet

BED1-42

KMB issued a tender for the purchase of double-decker electric buses in mid-2021, and the contract was eventually awarded to BYD for a fleet of 42 electric double-decker buses, each with a total capacity of up to 115 passengers.

In November 2022, a BYD B12D double-decker electric bus was rumored to have appeared at the BYD factory in Hangzhou, China. The electric bus used "Electric Green" as its main colour, with a scribbled version of the "Heartbeat of the City" logo on the left side of the body, and a glass curtain wall on the right side of the body, one of the buses in the batch with a lime green body arrived in Hong Kong on December 7Kowloon Motor Bus Company (1933) Ltd., "KMB received its first electric double-decker with 300 kilometres driving range, the highest in Hong Kong" [News Release], 7 December 2022., and was then transferred to the Tuen Mun General Repair Centre, where it was displayed at the [[KMB 90th Anniversary Carnival] held on 22 April, with the rest arriving in Hong Kong between June and July 2023.

The B12Ds have the following features:

Cabin

• The upper and lower halves of the driver's window are trip windows.
• The driving cab door was pre-installed with an anti-attack panel at the factory.
• The new Ventura pneumatic doors are painted brown, with switches on the outside of the drop doors, a larger headgate, and no hand drawer on the outside of the center door.
• A thicker guardrail was installed on the drop doors when the buses left the factory, and the position of the glass of the drop doors facing the guardrail was also blackened.
• The fire extinguishers are now placed above the front axle near the rear of the back cushion.
• The upper air-conditioning ducts continue to use spherical air outlets at the bottom, and the air vents next to the air-conditioning ducts and at the front end of the vehicle continue to use the exhaust air supply design, instead of using permeable air outlets.
• The lower air-conditioning ducts are designed with exhaust vents along the bottom and sides of the ducts, with ball vents at the front and rear ends, and with spotlights at the front.
• The stop announcement system screen uses the same long LCD as the BEB.
• Dynamic Passenger Information System display is installed above the alighting door.
• Dynamic Passenger Information System (DPS) LCD screens were installed behind the upper and lower staircases, but the DPS LCD screen was mounted at a higher position behind the upper staircase and the DPS LCD screen was placed at a reserved position behind the lower staircase.
• Backward-facing seats behind the upper staircase, with thick, straight handrail post near the window, handrail ring in the center above the backward-facing seat (but the equipment was removed after the inspection) and drop-off chime light.
• The T-shaped handrail post on each side of the upper front end was painted black near the wall, and the light gray handrail post and handrail ring were used on the whole car.
• Part of the handrail beside the staircase is the common pitched handrail of old buses.
• The right handrail post between the staircases is connected to the horizontal handrail post, replacing the horizontal handrail post, which is different from the handrail post design of the previous straight staircase buses.
• The handrail post at the rear of the driver's compartment on the lower deck is fitted with a trip bell and only the straight handrail post in the middle of the staircase on the upper deck is not fitted with a trip bell.
• All straight handrail posts on the lower deck are equipped with a trip bell and the straight handrail posts on the lower deck near the staircase are equipped with a trip bell.
• Installation of handrail posts and handrail rings for the opposite seats on the lower deck and horizontal handrail posts for the two upright handrail posts above the headrail.
• Lower rear seats are no longer fitted with hand restraints, but the middle rear seat retains the armrest posts and gray hand restraints.
• Two straight handrail posts have been added to the left side of the handrail posts along the stairway at the time of shipment.
• The glass panel is no longer installed on both sides of the door, and each side consists of a handrail array with a horizontal handrail post on the upper half and a beige fireproof plastic panel on the lower half, and the original handrail post on both sides of the door is replaced by a straight handrail post.
• The bell light on the upper deck is located on the right side of the station display screen, while the bell light on the lower deck is located on the left side of the station display screen.
• The lower level staircase is designed to have the lowest level of the staircase and the lower level staircase is designed to have the lowest level of the staircase and the lower level staircase is designed to have the highest level of the staircase.
• The lowest step of the staircase of this batch of buses was designed to be connected to the lower floor, unlike the previous design of double-deck buses where the staircase was raised by one step.
• Two wheelchair parking spaces and horizontal handrail columns have been provided at the factory. The right-hand side wheelchair parking spaces on the lower deck only occupies two rows of seats.
• There are two wheelchair parking areas with movable handrail posts.
• Orange LED lighting is installed underneath all near-aisle seats and between staircases.
• Beige LED lighting system throughout the interior, with auto dimming on the lower left side and no lighting above the drop doors.
• The upper deck has a slightly larger front fiber assembly, but the upper deck has no lighting system, but red crash pads (same as the Duple Metsec DM5000) are added to the front end.
• One piece of black reinforced glass is used for the emergency door, but it needs to be moved to the center of the front two axles; a breakable glass hammer is also attached to the outside of the vehicle (located to the right of the Pacific doors, above the rear axle).
• KMB re-installed the upper deck seat capacity indicator with infrared sensors at the Octopus fareboxes and upper deck staircases, and the number of seats remaining on the upper deck obtained from the sensors was immediately displayed on the screen at the lower deck near the staircases.
• Adopted the same wheelchair parking area near the alighting door with crash cushion in red colour same as that of M6EX, M6FX, V6X, and part of E6X.
• Two USB charging sockets are provided in the wheelchair parking spaces and on the wall next to all seats, and the LED light in the USB charging socket turns red when charging.
• Free 5G Wi-Fi service is available.
• Maintenance cover over the left wheelchair parking area on the lower deck and part of the upper deck air-conditioning duct, but with a larger drain opening on the upper deck.
• In response to the pillar-less design of the upper deck, the alighting bell have been relocated next to the individual air-conditioning vents.
• Beige and grey walls throughout the interior, with dark grey fiber components in the interior.
• Red wheelchair back cushions and stairwell crash cushions, and dark gray and apricot for the fire floor.
• Fainsa Cosmic seats were adopted for the whole bus, priority seat was also adopted in cream color and red color, and mini headrests were added to the upper deck rear seat near the escape window, which was again adopted for new buses after some of Scania K230UB, MAN 24.310 and Volvo B10TL, and all the seats were fitted with seat belts.
• Horizontal armrest post in the second wheelchair parking area and connected to the right side of the front armrest array of the caring seat, horizontal armrest post in the upper part and gray plastic plate in the lower part.
• Factory pre-installed ventilation windows on the upper and lower decks at the left side of the front and right side of the rear.
• Pre-installed driver assistance system, sleep alert system and GreenRoad quality driver monitoring system.

Bodywork

• Lower deck windows are significantly larger on both sides, same as MAN A95 buses.
• The front windshield has a different location for the water flap, which has been changed from under the windshield to under the electric license plate.
• The center lamps on both axles are built-in, and an additional lamp is installed at the rear of both sides.
• Air-conditioning system from Shanghai Songz Automobile Air Conditioning Co., Ltd was used
• Electronic Stability Program (ESP) is added to keep the car stable.
• New openmatics Driving Alert with rescue device was installed.
• Water-cooling system and battery management system to effectively manage the battery temperature and monitor the battery status, prolonging the battery life and improving the performance.
• Equipped with "feedback braking" system which converts part of the kinetic energy into electrical energy when decelerating, as a kinetic energy recovery.
• Equipped with dual motors "Wheel Side Drive System", the motors are installed in the wheels to drive the bus to save maintenance cost and free up space in the car.
• This batch of buses were the first to install automatic fire extinguishing device in the battery compartment.
• The third generation solar generating equippment and exhaust fan assembly were installed on the roof at the factory, and the roof is in green colour.
• The upper and lower front windshields are coated with blue blackout paint at the upper edges.
• The first bus has two licence plate positions on the body, one at the rear pump handle and the other to the right below the rear glass window, the same as KMB's Wright Eclipse Gemini and Wright Eclipse Gemini 2. The rear pump handle license plate position is canceled when the bus is licensed.
• The body was painted in the same "Electric Green" as BYD B12A 12m (BEB) as the main color of the body and roof, with red KMB lettering sprayed on the right side of the body, the front, the rear and the roof, and a black scribbled version of the "Heartbeat of the City" logo added on the left side of the body with glass walls, the near-skirt of the body and the rear of the body with the same colour as BYD B12A 12m (BEB). These buses are equipped with a glass curtain wall and black lines near the apron and wheel arches.
• The rear air-conditioning cover radiator is mounted with three horizontal aluminum panels in green colour.
• The air-conditioning radiator grills on both sides of the rear of the car have straight aluminum panels and are painted black.
• The right side of the rear battery motor radiator is designed with a straight aluminum plate and painted in electric green.
• Battery friction vent on the right side of the rear is designed with slanted aluminum sheet and painted in electric green.
• Black headlights and rear warning lights.
• The rear battery cover is equipped with a three-dimensional BYD logo.
• Lower deck with battery packs, thus reducing seating capacity by 8 seats compared to a typical diesel bus.
• Pre-factory change to Arcol electric mirror-mounted metal mirrors.
• New Hanover EG4 license plate controller installed in the cab, which is the latest generation with touch screen panel and new Hanover white HD displays.
• The upper door Long side destination sign is now placed above the window and the tailgate is placed above the air conditioning port.
• Ultrasonic detection points have been installed at the rear end and rear of the vehicle at the factory.
• Starting from this batch, the fleet number is no longer affixed to the buses and only the depot logo is displayed. The depot logo is also affixed to the front of the driver's panel assembly instead of the windscreen, and all newly registered buses only have the depot logo.

The first bus BED29/YT4393 was officially registered on 7 July 2023, and for the first time, it was not registered according to the fleet number order and was assigned to Kowloon Bay Depot (K), which was later debutted on Route 213M together with BED30/YT7813 on 30 July.

In 2023, BED23/YX4643, BED26/YV5853 and BED36/YV4494 were first operated on Route 234X route, but were suspended in the evening suspected to be due to unauthorised use of this bus on the route, until 13 November onwards when the Transport Department formally authorised the deployment.

On 28 November 2023, BED35/YX6348 was first operated on Route 62X. When the bus arrived at Tsui Ning Garden stop, all passengers were trapped for a while as the bus door could not be opened, and eventually left the bus after the door was forced open by the KMB engineering staff.

This batch of buses are currently scheduled to operate on routes 2, 5D, 6, 6D, 11, 24, 49M, 62X, 85K, 213M, 234X and 238X, occassionally running on routes 224X and 252 as orders.

This gallery saves only part of the images related to BYD B12D Only a limited number of representative images will be included in this gallery. To see more related images, please go to the Gallery:BYD B12D

Vehicle overview

The appearance of these buses (stairside)

The appearance of these buses (doorside)

The appearance of these buses (rear)

Interior layout

Lower deck layout (shown above was BED25/YV5907)

Lower deck layout (shown above was BED9/YV5976)

Upper deck layout (shown above was BED9/YV5976)

Upper deck layout (shown above was BED9/YV5976)

Upper deck rear-facing seats, with a beige handrail additionally installed on the seat near the corridor afterwards (shown above was BED9/YV5976)

Beige Fainsa Cosmic seats were used on these batch of buses這 (shown above was BED30/YT7813)

The lower-deck priority seats (shown above was BED9/YV5976)

The lower deck stop reporters (shown above was BED9/YV5976)

The upper deck stop reporters (shown above was BED9/YV5976)

Upper deck view of the staircase (shown above was BED9/YV5976)

Lower deck view of the staircase (shown above was BED9/YV5976)

The wheelchair parking space of this batch of buses (shown above was BED31/YV5934)

Fleet summary of KMB BYD B12D
Fleet no.	Body	Motor	Battery	Capacity	Year in service
BED1-41	BYD	BYD EQ13B	BYD	U55/L17+S43 115	2023-

Fleet list of KMB BYD B12D
Fleet no.	Plate no.	Current depot	Scheduled route	Destination sign	First registration date	Retirement date	Remarks
BED3	YX5925	S	Spare	Hanover II Electronic Destination Sign (White)	26-10-2023
BED5	YX5831	S	85K		26-10-2023
BED7	YX4528	L	238X		25-10-2023
BED8	YX4797	U	62X		26-10-2023
BED9	YV5976	L	6		31-08-2023
BED10	YX2652	S	85K		19-10-2023
BED12	YX1542	K	5D		17-10-2023
BED13	YX866	K	24		18-10-2023
BED14	YX3909	K	11		19-10-2023
BED15	YX3432	K	11		19-10-2023
BED19	YV3672	L	2		29-08-2023
BED20	YX6462	L	Spare		25-10-2023
BED23	YX4643	L	Spare		25-10-2023
BED24	YV6422	L	49M		30-08-2023
BED25	YV5907	L	6D		30-08-2023
BED26	YV5853	L	2		30-08-2023
BED29	YT4393	K	24		07-07-2023
BED30	YT7813	K	213M		19-07-2023
BED31	YV5934	K	5D		31-08-2023
BED32	YV2597	L	2		29-08-2023
BED35	YX6348	U	62X		26-10-2023
BED36	YV4494	L	234X		29-08-2023
BED37	YV6320	L	234X		31-08-2023
BED40	YX4108	S	85K		19-10-2023

Remarks

More pictures, photos and related information about this article are available in the following Gallery Page:

BYD B12D (Edit)

Related Articles

• Electric bus
• BYD Auto
• BYD B12A
• BYD K10

External Links

Official websites

• BYD Commercial Vehicles Official Website: B12D Model Pictures